Motor controller



Dec. 22, 1931.

EL H. LAABs MOTOR CONTROLLER .Filed Feb. 8, 1930 2 Sheets-Sheet Dec. 22, 1931.-"

E. H. LAABS l 1,837,224

MOTOR CONTROLLER Filed Feb. 8', 1930 2 Sheets-Sheet 2 y l, *je l//l/l/ ua/11111114000 L Patented-Dec. 22, 1931 y UNITED STATES PATENT ori-'ICE ERIC H. LAABS, F MILWAUKEE, WISCONSIN, ABSIGNOR TO CUTLER-HAIHER, INC., 0l'

' MILWAUKEE, WISCONSIN, A CORPORATION 0F DELAWARE no'ron CONTROLLER provided with a small and a large driving motor. The `small motor provides for operation of the press at a relatively low threading speed while the large motor rovides for operation thereof at higher s ee s, the small motor being then automatica 1y disconnected from its supply circuit and disengaged from the drive. In such installations 1t is necessary to operate the press by means of the large motor at relatively low take-off speeds so as to provide for equalization of the pull on the web duringl acceleration and to also enable the operator to make the necessary margin adjustments. However, it has heretofore been difficult to control the large motor so as to provide the required low take-off speeds and at the same time maintain the torque required for starting, this being espec1ally true in high speed printing presses employing A. C. motors.

The present invention has among its objects to provide an improved controller which is partlcularly adapted for use in connection with high speed A. C. printing presses and which provides for operation of the 3o large motor at one or more relatively low take-off speeds and also insures a relatively high starting torque.`

Various other objects and advantages of the invention will hereinafter appear.

The accompanying drawings illustrate an embodiment of the invention which will now be described, it being understood that the embodiment illustrated is susceptible of modilication without departing from the spirt and scope of the appended claims.-

In the drawings y Figure 1 diagrammatically illustrates a controller embodying the invention.

Fig. 2 diagrarnlnatically illustrates the large and small driving motors and the circuit connections therefor, and

Fig. 3 schematically illustrates a control device employed in the' system shown in Fig. 1.

The controller illustrated in Fig. 1 provides for control of a printing press drive including a small motor M1 and a large motor M2, said motors bein shown in Fig. 2.v Motors M1 and M2 are o a three phase alternatingcurrent type and 'Y electroresponsive switches 1 and 2 are provided for selectively connecting the same to a supply circuit indicated by lines L1-L2-L3. The speed of the large motor M2 is controlled by means of resistances R1 to R5, inclusive,` which are connected in the secondary circuit thereof. As hereinafter set forth resistances R211z and Ra are controlled by a` rheostat 3 while resistances R* and R5 are controlled by an electroresponsive switch 4.

As shown in Fig. 1 the control means for switches 1, 2 and 4 and rheostat 8 includes an on relay 10, an off relay 11, an inch relay 12, a stop relay 13, a reset relay7 14, a safe after inch relay 15 and a safe relay 16. Each of said relays is provided with an operating winding designated by reference character a and each, with the exception of the safe after inch relay, has a control switch located at a push button station 17. The control switch for the safe relay 16 is of a two button snap operatin type while the other control switches are o the normally open push button type.

Rheostat 3 is of the crosshead type and as shown in Fig. 1 the same is provided with a driving motor M3 having an armature A and a series field winding F. The crosshead of rheostat 3 is provided with a bridging contact 20 which cooperates with a plurality of auxiliary contacts 2l to 27, inclusive. Also, as

shown in Fig. 2, said crosshead is'provided with insulated main contacts 28, 29' and 30 which are electrically connected to each other and cooperate with three sets of stationary contacts 31, 32 and 33, associated with resistances R1, R2, and As hereinafter set forth the rheostat motor M3 has means associated therewith for eiiecting step by step operation thereof. Such means includes normally op en limit switches 34 and 35 which are associated with the operating mechanism of the rheostat and are adapted to close immediately upon starting of `the motor M8 and to reopen upon a. given degree of operation of nlA pump l0 ci a well known type which is essuch motorn Rheostat 3 also, has a limit switch 3 associated therewith which is adapted to open in the off position of the crosshead.

In addition to the aforedescribed control means the controller includes normally open auxiliary contacts 36 and normally closed auxiliary contacts 37 associated with switches l and 2 and normally closed switches 38 and 39 which are adapted to control switch l and are associated with a speed responsive device fhich may be of the character shown in 3i.

The device sho-wn in lEig. l includes gear sociaed 'with the press drive to be drm thereby luinp Ll() is arranged within a c ing il containing a :fluid d2 such as oil, and pump is driven a direction whereby the 4,duid 42 enters the casing olf said pump through an opening d3 and is discharged through an opening into cylinder d5 ned to casing all. Cylinder Ll5 contains a piston d6 which is biased downwardly by an adjustable spring l? and normally covers an outlet port 48 in 'said cylinder d5.. Switches 38 and 39 are operatively connected to said piston to be opened'thereby upon upward movement thereof. As is apparent, when fluid is delivered by thepump 40 to cylinder l5 the piston d6 is held in a raised position to permit escape ci the duid throu h the port d8. Obviously the position of piston le is determined by the speed at which pump ll() is driven, and the arrangement is such that said piston effects opening ci switches 38 and 39 when thespeed of the press exceeds different predetermined values.

The operation of the aforedescribed controller and the circuit connections therefor will nonr be more fully described. With the cross head ot rheostat 3 in the oft" position or in position l indicated by dotted lines in F ig. 1 the small rnc-tor switch l is adapted to be energized by the inch relay l2 through the medium of the stop relay 13.l Such energizing circuit extends from line Z1 through contacts 12b of the inch relay to contact 22 ci rheostat 3, through bridging contact 20 to contact 24 of said rheostat to and through the operating winding l of the small motor switch, by conductor 50 through contacts i3 of the stop relay and by conductor 5l to line l Upon response of the small motor switch 1 contacts 36 close and with the rheostet crosshead in position l, a maintaining ein cuit for said switch is established extending from line Z1 by conductor 52 through auxiliary contacts 36, by conductor 53 to contact 2l oi rheostat 3 through bridging contact 20 to contact 24 of said rheostat and through the opu era-ting Winding l of the small motor switch to line Z2 as already traced. Closure of switch l connects the small motor M1 to lines 'L1-422- B and said motor is adapted to `operate the press at a relatively low 'thread- 'operating winding 2 ci the large motor switch is connected in parallel the operating winding ln of the small motor switch through the medium nl contacts 21,2() and 23 ct the rheostat. ilse switch i is connected in parallel with the op ing winding. le of the small motor switch t ugh the medium of contacts 2l, 2^ ont; ci. the rheos .t switch rlhus with r i f ill-20F L tion 2 the 2 are both connected to lines l lf ane. the motor accelerates with resistances Z-ll included in the secondary circuit thereof and resistances and R5 excluded from such circuit by switch fl. Upon speeding up of the press by motor M2, motor lill is automatically disconnected from the press drive by mechanism ol the type usually employed for this purpose in two motor print ing press systems. When the speed of the large motor exceeds a given `value device All opens switch 38 and switch l is thus deenergiaed to include resistances Rt and Tt in the secondary circuit oi motor ld. Motor M2 then slows downand switch 38 recloses to again energize switch ll for reinclusion ci? resistances litL and ll in the secondary circuit ci? motor M2. rlhe resistance in the secondary .circuit ot the large motor lli/ is thus periodi cally increased and decreased to provide for operation of said motor at a substantially constant speed which is determined by the speed required to effect o ening of switch The press speed thus o tained may be oi relatively low value, as for example 'l5 P. M. to enable the operator to malte the neces sary margin adjustments. Also as is apparent, such relatively low press speed permits equalization ci the pull on the web to prevent breakage thereof.

Upon movement oi the crosshead of rheostat 3 into its third dotted line position bridging contact 2G disengages contact to interI` rupt the aforedescribed energizing circuit for the small motor switch l, the large motor switch being maintained energized hereinf before described. Also upon movement of the crosshead into this position bridging con 'tact 20 disengages contact and 2 is maintained energized as hereinbefore described and switch 4 is maintained energized through the medium of bridging contact 20 and contact 27 of said rheostat.

Motor M2 then operates to accelerate the press to a higher intermediate speed, as for example 125 R. P. M., such speedbeing determined by the value of resistances R1-R2 and R3.

As is apparent from Fig. 2, by continuing upward movement of the crosshead of rheostat 3, resistances R1, R2 and R2 are excluded from the secondary circuit of motor M2 to bring said motor up to a maximum speed.

The on relay lO'provides for operation of the ilot motor M2 in a direction to effect upwar movement of the crosshead of rheostat 3 while the ofi relay 11 provides for operation of said motor in a reverse direction for Ydownward movement of said crosshead. Upon closure of either the small motor switch 1 or the large motor switch 2 on relay 10 provides for establishment of an energizing circuit for the pilot motor M2 extending from line Z1 by conductor 52 through auxiliary contacts 36'by conductor 53 to rheostat contact 21 by conductor 55 through contacts 10b of the on relay by conductor 56 through the armature Afrom left to right and through a resistance r1 and the field winding F to line Z2. The off relay 11 provides for establishment of an energizing circuit for the pilot motor M2 extending from line Z1 b conductor 57 through-contacts 11b of sai relay through the armature A from right to left and thence through 'a resistance 'r2 and field winding F to -line Z2.

The controller is inoperative except upon closure of the safe relay 16,-and as is apparent from Fig. 1 the operating winding of said relay is connected across line Z1-Z2 upon closure of the safe switch of push button station 1 7.

As hereinbefore set forth when the rheostat crosshead is in off position the small motor switch 1 is adapted to be energized through the medium of the inch rela 12 and stop relay 13. Closure of the inch push button establishes an energizing circuit for the inch` relay extendingfrom line Z1through f said push button byconductor 58 through the operating winding 12B of said relay by conductors 59 and 60 through the safe relay to line Z2. The stop relay 13 is dependent forv energization upon closure of the reset relay 14. Closure of the reset push butt-on y y circuit for the reset relay 14 extending rom line Z1through as already traced.

said push button to and through the o 'rj ating winding 14'* of said relay, by con uctor 60 through the safe relay 16 to line Z2.

Closure of the res/et relay 14 establishes an energizing circuit for the fstop relay 13 extending from line Z1 by' conductor 61 through relay 14 by'conductor 62 through the operating winding 13 of the stop relay by conductor 63 through a resistance r2 and by conductors 64 and 51 to line Z2. In responding the stop relay 13 maintains itself by a circuit extending from line Z1 by conductor 65 through contacts 13'1 of-said rela and through the operatin winding 13'* to lme Z2 pon response of the inch relav 12 the safe after inch relay 15 is energized by a circuit extending from line Z1 by conductor 66 through contacts 12d of the inch relay through the operating winding 152 of the safe after inch relay, through contacts 13 of the stop relay and by conductor 51't0 line Z2. The safe after inch relay in responding maintains itself by a circuit extendingfrom line Z1 by conductors 66 and 67 through contacts 15c and thence through the operating winding 15 to line Z2 y upon release of such push button. Following inching operations the stop rela drops out, the operating winding thereo shunted by a circuit extending from line Z1 b conductor 52 through auxiliary contacts 37 by conductor 68 through contacts 15b of the safe after inch relay through normally closed contacts 12c of the inch relay by conductors 69 and 70 through resistances 1'* and r2 and by conductors 64 and 51 to line Z2. C ening of the stop relay 13 interrupts the a oredescribed energizing circuit for the safe after inch relay 15. Thus'after inching operations it is necessary to effect operation of the reset relay 14 as a prerequsite to reclosure of the stop relay 13.

being Upon depression of the on push butl ton the on relay 10 is energized by a circuit extending from line Z1 through said push button 'to and through the operating winding 10 of said relay and by conductors 71 and 60 through the safe relay 16 to line Z2. The on relay 10 in responding establishes an energizing circuit for the inch relay 12 extending from line Z1L by conductor 52 through contacts 13" of the stop relay by conductor 7 2 through contacts'lOl of the on relay by conductor 58 to and through the operating winding 12 of the inch relay by conductors 59 and 60 through safe relay 16 to line Z2. As hereinbefore set forth upon closure of the inch relay 12 and the-on relay 10 pilot motor Ms is operated in a direction to effect u ward movement of the rheostat crosshead. lUponl initial upward movement of the o tl lio

rheostat crosshead limit switch 34 closes and the onf relay l10 is then maintained energized by a circuit extending from line Z1 by conductor 52 through contacts 13b of the stop relay through contacts 10 of the on relay by conductor 73 through' limit switch 34 by conductor il through the operating Winding lll of the on relay and by conclue tors 7l ond 60 through soie relcy lo to line i2. Limit switch Sel opens to iuterruiot the maintaining circuit for the on relay l@ upon given degree ol coercition ol the pilot motor MS. Thus provision is inode lor el looting upworld movement the rheostct erossheed in s step by step manner upon successive operations ot the ou push button., it

being` assumed that the limit switch Bil operu etes to et'lect arrest olthe crossheod io the positions indicated by dotted iii lig.. l.

Bepression oit the stop push button loro vides 'tor return o the crossheod ont the rhoestet to ed' position., Upon depression ol 'the stop push button operating Winding i3@ el the stop relay is shunted by n circuit entendingjg from line l1 through seid stop push button by conductor through tesis-tonces Rt ond R3 and by conductors @il ond il operation oi the large motor M2 return ol seid crossheod towards ofi position in o by step manner is eected by successive operotions ol the oil push button. Closure oil the oil push button establishes on energizing circuit for the operating' windingolt the oli relay ll extending; from line l1 through said push buttonby conductor 78 'through uuifiliery contacts 2b associated with the large motor switch 2 by conductor 'i9 to und through the operating Winding lllm ol the ci@ relay and thence through the limit switch 3a to line l2. Upon initial downward movenient of 'the rheostot crosshecd switch 35 closes to establish a moiutnining circuit for the operating winding o'l the ed relay ex-A tending .fromline l1 by conductor 52 through contacts 11 of the ed reley to and through switch 35i-by conductors 8O and 79 to and through the operating winding ll of the off relay and thence through limit switch 3 to line Z2 as already traced. Limit switch 35 opens to interrupt the atoredescribed mainteinmg circuit for the oil relay 11 upon o given degree of operation of the pilot motor M8.

What I claim es new and desire to secure by Letters Potent is: y

1. The combination 'with e driveincluding o mein motor and en auxiliary motor9 oli control menos for soidmotors operable to lirst stort seid ouniliory'motor ood to thereoiter stort seid moin motor, seid control moons providing for operotion oi scid moin motor et o relotively high speed.. und moons ossocicted with scid control .ineens und in cluding u. device responsive to ,given speed vorietions ol seid motor lor restriotiisg7 C letter 'to operotion o predetermined substontielly constant low speed.

2. The combioetion with drive includin e main and on ouniliory motor9 oli control ineens lor scid motors operable to stort seid euxilisry motor sindv thereoio seid nmin motor for operotiou relatively high speed, und ineens controlled by seid loriner ineens end including s device responsive to variations in the speed ol seid moin motor lor restricting the letter one oi o plurality ol low selectively occording1 to the setting oi e port ol seid first mentioned control resem,

3. The combination with drive includ ing :i .moin .motor und ouuilisry mot oi o control device lor solo. rosters movable into :i `@given position to stort seid suvilicry motor und into another position to et ct oper tion oi seid moin motor et relatively high speed ond ineens responsive to gir/'eo speed veristions ol seid moin otor ond operable in the lost meutioned por on ot seid control. devies 'to restrict seid mein rector to operation o predetermined substontiolly constont low speed.

d. rThe combination with s drive7 including e moin induction motor codon auxiliary induction motor, ol o common control device lor seid motors edefited in given position to stort seid ouxiliory motor sind in smother position to stort seid moin motor, c plurality ci" resistences to be included in the secondary circuit oi seid motor, certoin ol scid, resistences being associated with seid control device ond providing for operution olf scid main motor et c reletiyel high speed dii lill? lll) lib

upon stortioggr ther-col by sui device ond 1 ineens res onsive to the .speed oit scid moin motor en adopted to'oct in o given posi tion oil seid device to 4control the other ol seid resistences 'to restrict seid .moin motor to e predetermined suhstentinlly constant lovr las y given speed variations of said main motnr and adapted to act in certain of the latter positions of said control device to restrict said main motor to different predetermined sub- 6 stantially-constant low speeds selectively.

6. The combination with a drive including a main induction motor and an auxiliary induction motor, of a control device for said motors movable inl a step by step manner 10 into a given position to start said auxiliary motor and into other positions to eect operation of said main motor, a plurality of resistances, certain to be included in the seconda circuit of said main motor in the latter posivlli tions of said device to provide for o ration of said main motor at a relatively big speed, andmeans ada ted to act in thelatter positions of said evice to riodically include and exclude the Aother oiesaid resistances in Y zo accordance with given speed variations of said main motor to selectively provide for opq eration of said main motor at different predetermined substantiall constant low speeds.

In witness whereof, have hereuntol subv 25 scribed my name. ERIC H. LAABS. 

